EP0919702A2 - Process for reducing the NOx content of Diesel engine exhaust gas - Google Patents

Process for reducing the NOx content of Diesel engine exhaust gas Download PDF

Info

Publication number
EP0919702A2
EP0919702A2 EP98119867A EP98119867A EP0919702A2 EP 0919702 A2 EP0919702 A2 EP 0919702A2 EP 98119867 A EP98119867 A EP 98119867A EP 98119867 A EP98119867 A EP 98119867A EP 0919702 A2 EP0919702 A2 EP 0919702A2
Authority
EP
European Patent Office
Prior art keywords
exhaust gas
catalyst
internal combustion
combustion engine
catalyst efficiency
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP98119867A
Other languages
German (de)
French (fr)
Other versions
EP0919702A3 (en
Inventor
Gerhard Dr. Wissler
Lothar Hofmann
Günther Dr. Pajonk
Manfred Weigl
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Siemens AG
Siemens Corp
Original Assignee
Siemens AG
Siemens Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens AG, Siemens Corp filed Critical Siemens AG
Publication of EP0919702A2 publication Critical patent/EP0919702A2/en
Publication of EP0919702A3 publication Critical patent/EP0919702A3/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion
    • F01N3/206—Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents
    • F01N3/2066—Selective catalytic reduction [SCR]
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D21/00—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas
    • F02D21/06—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air
    • F02D21/08—Controlling engines characterised by their being supplied with non-airborne oxygen or other non-fuel gas peculiar to engines having other non-fuel gas added to combustion air the other gas being the exhaust gas of engine
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D31/00—Use of speed-sensing governors to control combustion engines, not otherwise provided for
    • F02D31/001—Electric control of rotation speed
    • F02D31/007—Electric control of rotation speed controlling fuel supply
    • F02D31/008—Electric control of rotation speed controlling fuel supply for idle speed control
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/02—Circuit arrangements for generating control signals
    • F02D41/021—Introducing corrections for particular conditions exterior to the engine
    • F02D41/0235—Introducing corrections for particular conditions exterior to the engine in relation with the state of the exhaust gas treating apparatus
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D41/00—Electrical control of supply of combustible mixture or its constituents
    • F02D41/30—Controlling fuel injection
    • F02D41/38—Controlling fuel injection of the high pressure type
    • F02D41/40—Controlling fuel injection of the high pressure type with means for controlling injection timing or duration
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N2430/00—Influencing exhaust purification, e.g. starting of catalytic reaction, filter regeneration, or the like, by controlling engine operating characteristics
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N2610/00—Adding substances to exhaust gases
    • F01N2610/02—Adding substances to exhaust gases the substance being ammonia or urea
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
    • F02D—CONTROLLING COMBUSTION ENGINES
    • F02D2250/00—Engine control related to specific problems or objectives
    • F02D2250/36—Control for minimising NOx emissions
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/40—Engine management systems

Definitions

  • the invention relates to a method for reducing the NO x content in the exhaust gas of a diesel engine according to the preamble of claim 1.
  • the so-called S elective- C atalytic- R eduction technique is known.
  • a reducing agent is injected into the exhaust gas at a point in front of a catalytic converter and NO x contained in the exhaust gas is thus reduced to N 2 .
  • Ammonia can be used as the reducing agent; for reasons of manageability, an aqueous solution of urea is usually used (for example DE 44 36 415 A).
  • the control unit of the diesel engine continuously the target amount of reducing agent metering calculated.
  • the control unit requires the current catalyst efficiency. This is made up of operating parameters and the catalyst temperature.
  • the catalyst temperature in turn, for example, through a model calculation from the exhaust gas temperature and the exhaust gas mass flow be determined.
  • the effectiveness of the exhaust gas treatment depends on the catalyst temperature. 3 shows a typical course of the catalyst efficiency as a function of the catalyst temperature. In the temperature range around 250 ° C, the catalyst efficiency with which the NO x reduction takes place becomes maximum and drops sharply towards lower temperatures. The catalyst efficiency drops to zero at temperatures below 120 ° C.
  • the dosing may only be carried out if the exhaust gas temperature is high enough for the decomposition of urea to form the ammonia required for the catalytic conversion.
  • the decomposition of urea is supported catalytically and begins at temperatures above 130 ° C. Lower temperatures therefore mean that firstly no reducing agent can be metered in and secondly that the catalyst has no effect.
  • the catalytic exhaust gas treatment in a diesel internal combustion engine, especially for NO x reduction, is ineffective immediately after the cold start.
  • the catalytic reaction does not start until the exhaust gas temperature rises.
  • the exhaust gas cools down relatively quickly, so that, for example, when accelerating a vehicle after downhill gradients, the catalytic NO x reduction is virtually ineffective, which results in an undesirably high NO x emission.
  • the catalyst efficiency is calculated from engine data such as air mass, operating temperature or load. With the SCR principle, these calculations are required for the supply of reducing agent. Taking this catalyst efficiency into account, intervention in the control parameters, in particular the start of injection, the course of injection, the exhaust gas recirculation rate or valve control, can reduce the NO x emissions at the expense of minimizing consumption. By intervening in the control parameters, the NO x content in the untreated exhaust gas is reduced on the one hand and the exhaust gas temperature is increased more quickly by reducing the efficiency of the diesel internal combustion engine, which in turn increases the efficiency of the catalytic converter. The lower efficiency in the case of a cold internal combustion engine can be accepted, since measures are required anyway for rapid heating of the internal combustion engine for reasons of comfort.
  • the diesel engine 3 has an intake tract 9, one Injection system 2 and an exhaust tract 4.
  • a catalytic converter 8 based on the SCR principle works, arranged.
  • This catalyst 8 is a metering device, consisting of a reducing agent supply 5 and a metering valve 6, upstream. From the reducing agent supply 5 is via the metering valve 6 urea as a reducing agent injected into the exhaust gas upstream of the catalyst 8.
  • the metering valve 6 is not specified Lines controlled by a control unit 1.
  • For surveillance and control of the reducing agent dosage is one Sensor 7 provided that the heat of vaporization of the injected Reductant measures.
  • the control unit 1 of the diesel engine 3 controls via unmarked lines the injection system 2. Furthermore, the diesel engine has 3 via a system for exhaust gas recirculation as well switching off the fuel supply in overrun mode (not shown).
  • Curve A shows the temporal speed curve, specified by a test specification (MVEG test cycle), with which a test vehicle drives after a cold start.
  • Curve B shows the time course of the catalyst temperature in an exhaust gas aftertreatment according to the prior art.
  • Curve C shows the course over time of the catalyst temperature in the process according to the invention for reducing the NO x content.
  • the speed course of the MVEG test cycle is like follows: First, a speed profile typical for city traffic with repeated acceleration, braking and drive through standstill. An exemplary acceleration phase is denoted by b, an overrun phase by s. After 700 seconds are driven at higher speeds.
  • Curve B shows the course of the catalyst temperature, which, as is known from FIG. 3, is linked to the catalyst efficiency in the case of a catalyst based on the SCR principle. It can be clearly seen that the temperature drops during phases of braking or when the test vehicle is at a standstill. That is, the efficiency of the catalytic after-treatment also falls, thus increasing a NOx content in the treated exhaust gas is accompanied. The temperature at which the addition of reducing agent can be started according to the SCR principle is only exceeded after 300 seconds.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Exhaust Gas After Treatment (AREA)
  • Output Control And Ontrol Of Special Type Engine (AREA)

Abstract

Bei einer Dieselbrennkraftmaschine mit katalytischer Abgasbehandlung nach dem SCR-Prinzip wird aus dem für die Dosierung des Reduktionsmittels berechneten Katalysatorwirkungsgrad von einem Steuergerät ein zu hoher NOX-Ausstoß erkannt und dann Maßnahmen wie verzögerter Beginn der Kraftstoffeinspritzung, Deaktivieren einer Schubabschaltung, Verringern einer Abgasrückführrate und/oder Erhöhen der Leerlaufdrehzahl eingeleitet. Dadurch sinkt der NOX-Gehaltes im unbehandelten Abgas, die Katalysatortemperatur (C) steigt nach einem Kaltstart schneller an und der NOX-Ausstoß wird reduziert.

Figure 00000001
In a diesel internal combustion engine with catalytic exhaust-gas treatment according to the SCR principle, too high NO X emissions is detected from the calculated for the dosing of the reducing agent catalyst efficiency of a control device, and then measures such as delayed start of fuel injection, disable a fuel cut, reducing an exhaust gas recirculation rate and / or increasing the idle speed. As a result, the NO x content in the untreated exhaust gas drops, the catalytic converter temperature (C) rises more quickly after a cold start and the NO x emissions are reduced.
Figure 00000001

Description

Die Erfindung betrifft ein Verfahren zur Verringerung des NOX-Gehaltes im Abgas einer Dieselbrennkraftmaschine gemäß dem Oberbegriff des Anspruchs 1.The invention relates to a method for reducing the NO x content in the exhaust gas of a diesel engine according to the preamble of claim 1.

Zur Verringerung des NOX-Gehaltes im Abgas einer Dieselbrennkraftmaschine ist das sogenannte Selective-Catalytic-Reduction-Verfahren bekannt. Dabei wird an einer Stelle vor einem Katalysator ein Reduktionsmittel in das Abgas eingespritzt und so im Abgas enthaltenes NOx zu N2 reduziert. Als Reduktionsmittel kann Ammoniak verwendet werden, aus Gründen der Handhabbarkeit wird üblicherweise eine wässrige Lösung von Harnstoff eingesetzt (z. B. DE 44 36 415 A).In order to reduce the NO x content in the exhaust gas of a diesel internal combustion engine, the so-called S elective- C atalytic- R eduction technique is known. In this case, a reducing agent is injected into the exhaust gas at a point in front of a catalytic converter and NO x contained in the exhaust gas is thus reduced to N 2 . Ammonia can be used as the reducing agent; for reasons of manageability, an aqueous solution of urea is usually used (for example DE 44 36 415 A).

Beim Harnstoff SCR-System wird vom Steuergerät der Dieselbrennkraftmaschine fortlaufend die Sollmenge der Reduktionsmitteldosierung berechnet. Dazu benötigt das Steuergerät den momentanen Katalysatorwirkungsgrad. Dieser wird aus Betriebsparametern und der Katalysatortemperatur bestimmt. Die Katalysatortemperatur wiederum kann beispielsweise durch eine Modellrechnung aus der Abgastemperatur und dem Abgasmassenstrom ermittelt werden.In the urea SCR system, the control unit of the diesel engine continuously the target amount of reducing agent metering calculated. The control unit requires the current catalyst efficiency. This is made up of operating parameters and the catalyst temperature. The catalyst temperature in turn, for example, through a model calculation from the exhaust gas temperature and the exhaust gas mass flow be determined.

Die Wirksamkeit der Abgasbehandlung hängt von der Katalysatortemperatur ab. Fig. 3 zeigt einen typischen Verlauf des Katalysatorwirkungsgrades als Funktion der Katalysatortemperatur. Im Temperaturbereich um 250°C wird der Katalysatorwirkungsgrad, mit dem die NOX-Reduktion erfolgt, maximal und fällt zu niedrigeren Temperaturen hin steil ab. Der Katalysatorwirkungsgrad geht bei Temperaturen unterhalb 120°C gegen Null. Bei der Verwendung von wässeriger Harnstofflösung als Reduktionsmittel darf die Dosierung nur erfolgen, wenn die Abgastemperatur für die Zersetzung von Harnstoff zur Bildung des für die katalytische Umwandlung nötigen Ammoniaks hoch genug ist. Die Zersetzung von Harnstoff wird katalytisch unterstützt und beginnt bei Temperaturen über 130°C. Niedrigere Temperaturen bedeuten also, daß erstens kein Reduktionsmittel dosiert werden kann und zweitens der Katalysator wirkungslos ist.The effectiveness of the exhaust gas treatment depends on the catalyst temperature. 3 shows a typical course of the catalyst efficiency as a function of the catalyst temperature. In the temperature range around 250 ° C, the catalyst efficiency with which the NO x reduction takes place becomes maximum and drops sharply towards lower temperatures. The catalyst efficiency drops to zero at temperatures below 120 ° C. When using aqueous urea solution as a reducing agent, the dosing may only be carried out if the exhaust gas temperature is high enough for the decomposition of urea to form the ammonia required for the catalytic conversion. The decomposition of urea is supported catalytically and begins at temperatures above 130 ° C. Lower temperatures therefore mean that firstly no reducing agent can be metered in and secondly that the catalyst has no effect.

Die katalytische Abgasbehandlung bei einer Dieselbrennkraftmaschine, speziell zur NOX-Reduktion, ist unmittelbar nach dem Kaltstart unwirksam. Erst mit steigender Abgastemperatur setzt die katalytische Reaktion ein. Im schubbetrieb kühlt das Abgas relativ schnell wieder ab, so daß z.B. beim Beschleunigen eines Fahrzeuges nach Gefällstrecken die katalytische NOX-Reduktion nahezu unwirksam ist, was einen unerwünscht hohen NOX-Ausstoß zur Folge hat.The catalytic exhaust gas treatment in a diesel internal combustion engine, especially for NO x reduction, is ineffective immediately after the cold start. The catalytic reaction does not start until the exhaust gas temperature rises. In the overrun mode, the exhaust gas cools down relatively quickly, so that, for example, when accelerating a vehicle after downhill gradients, the catalytic NO x reduction is virtually ineffective, which results in an undesirably high NO x emission.

Es ist somit Aufgabe der vorliegenden Erfindung, ein Verfahren zur Verringerung des NOX-Gehaltes im Abgas einer Dieselbrennkraftmaschine mit Abgasnachbehandlung nach dem SCR-Prinzip anzugeben, das bei zu niedrigen Katalysatortemperaturen den Katalysatorwirkungsgrad schneller erhöht.It is therefore an object of the present invention to provide a method for reducing the NO x content in the exhaust gas of a diesel internal combustion engine with exhaust gas aftertreatment according to the SCR principle, which increases the catalyst efficiency more quickly when the catalyst temperatures are too low.

Die genannte Aufgabe wird mit den Merkmalen des Patentanspruchs 1 gelöst. Vorteilhafte Weiterbildungen sind in den Unteransprüchen gekennzeichnet.The stated object is achieved with the features of the patent claim 1 solved. Advantageous further developments are in the Subclaims marked.

Aus Motordaten, wie Luftmasse, Betriebstemperatur oder Last wird der Katalysatorwirkungsgrad berechnet. Beim SCR-Prinzip sind diese Berechnungen zur Reduktionsmittelzuführung erforderlich. Unter Berücksichtigung dieses Katalysatorwirkungsgrades kann durch Eingriff in die Steuerungsparameter, insbesondere Einspritzbeginn, Einspritzverlauf, Abgasrückführrate oder Ventilsteuerung, der NOX-Ausstoß zu Lasten der Verbrauchsminimierung reduziert werden. Durch den Eingriff in die Steuerungsparameter wird zum einen der NOX-Gehalt im unbehandelten Abgas verringert und zum anderen durch die Reduzierung des Wirkungsgrades der Dieselbrennkraftmaschine die Abgastemperatur schneller erhöht, was wiederum den Katalysatorwirkungsgrad steigert. Der geringere Wirkungsgrad bei kalter Brennkraftmaschine kann akzeptiert werden, da aus Komfortgründen ohnehin Maßnahmen für eine schnelle Erwärmung der Brennkraftmaschine gefordert werden.The catalyst efficiency is calculated from engine data such as air mass, operating temperature or load. With the SCR principle, these calculations are required for the supply of reducing agent. Taking this catalyst efficiency into account, intervention in the control parameters, in particular the start of injection, the course of injection, the exhaust gas recirculation rate or valve control, can reduce the NO x emissions at the expense of minimizing consumption. By intervening in the control parameters, the NO x content in the untreated exhaust gas is reduced on the one hand and the exhaust gas temperature is increased more quickly by reducing the efficiency of the diesel internal combustion engine, which in turn increases the efficiency of the catalytic converter. The lower efficiency in the case of a cold internal combustion engine can be accepted, since measures are required anyway for rapid heating of the internal combustion engine for reasons of comfort.

Bei Otto-Motoren ist es aus

Figure 00030001
Bewertung der stöchiometrischen Benzindirekteinspritzer-Motorentechnologie", AVL-Tagung Motor und Umwelt, 1997, S. 106 f. bekannt, den Einspritzzeitpunkt auf Kosten von Kraftstoffmehrverbrauch zu verzögern, um die Stickoxidemissionen zu reduzieren.It's over with Otto engines
Figure 00030001
Evaluation of the stoichiometric gasoline direct injection engine technology ", AVL-Tagung Motor und Umwelt, 1997, p. 106 f. Known to delay the injection timing at the expense of additional fuel consumption in order to reduce nitrogen oxide emissions.

Im folgenden wird die Erfindung anhand der Zeichnung näher beschrieben. Die Zeichnung zeigt:

Fig. 1
eine schematische Darstellung einer Dieselbrennkraftmaschine mit katalytischer Nachbehandlung des Abgases nach dem SCR-Prinzip,
Fig. 2
ein Diagramm mit dem zeitlichen Verlauf der Katalysatortemperatur bei einem Testfahrzeug, das einen bestimmten Geschwindigkeitsverlauf durchfährt und
Fig. 3
einen Verlauf des Kataylsatorwirkungsgrades als Funktion der Katalysatortemperatur.
The invention is described in more detail below with reference to the drawing. The drawing shows:
Fig. 1
1 shows a schematic representation of a diesel internal combustion engine with catalytic aftertreatment of the exhaust gas according to the SCR principle,
Fig. 2
a diagram with the temporal course of the catalyst temperature in a test vehicle, which runs through a certain speed curve and
Fig. 3
a curve of the catalyst efficiency as a function of the catalyst temperature.

In Fig. 1 ist eine Dieselbrennkraftmaschine 3 dargestellt. Die Dieselbrennkraftmaschine 3 weist einen Ansaugtrakt 9, eine Einspritzanlage 2 und einen Abgastrakt 4 auf. Im Abgastrakt 4 ist ein Katalysator 8, der nach dem SCR-Prinzip arbeitet, angeordnet. Diesem Katalysator 8 ist eine Dosiereinrichtung, bestehend aus einer Reduktionsmittelzufuhr 5 und einem Dosierventil 6, vorgelagert. Aus der Reduktionsmittelzufuhr 5 wird über das Dosierventil 6 Harnstoff als Reduktionsmittel in das Abgas stromauf des Katalysators 8 eingespritzt. Das Dosierventil 6 wird über nicht näher bezeichnete Leitungen von einem Steuergerät 1 angesteuert. Zur Überwachung und Steuerung der Reduktionsmitteldosierung ist ein Sensor 7 vorgesehen, der die Verdampfungswärme des eingespritzten Reduktionsmittels mißt. Das Steuergerät 1 der Dieselbrennkraftmaschine 3 steuert über nicht bezeichnete Leitungen die Einspritzanlage 2. Weiter verfügt die Dieselbrennkraftmaschine 3 über ein System zur Abgasrückführung sowie eine Abschaltung der Kraftstoffzufuhr im Schubbetrieb (nicht dargestellt).1 shows a diesel internal combustion engine 3. The diesel engine 3 has an intake tract 9, one Injection system 2 and an exhaust tract 4. In the exhaust system 4 is a catalytic converter 8 based on the SCR principle works, arranged. This catalyst 8 is a metering device, consisting of a reducing agent supply 5 and a metering valve 6, upstream. From the reducing agent supply 5 is via the metering valve 6 urea as a reducing agent injected into the exhaust gas upstream of the catalyst 8. The metering valve 6 is not specified Lines controlled by a control unit 1. For surveillance and control of the reducing agent dosage is one Sensor 7 provided that the heat of vaporization of the injected Reductant measures. The control unit 1 of the diesel engine 3 controls via unmarked lines the injection system 2. Furthermore, the diesel engine has 3 via a system for exhaust gas recirculation as well switching off the fuel supply in overrun mode (not shown).

Das Steuergerät 1 bestimmt den Katalysatorwirkungsgrad und den NOX-Gehalt im unbehandelten Abgas der Dieselbrennkraftmaschine 3 wie folgt:

  • Einem Kennfeld wird abhängig von Abgastemperatur und Abgasmenge vor dem Katalysator der Katalysatorwirkungsgrad entnommen. Dazu wird die Abgasmenge aus der Ansaugluftmasse bestimmt; sie kann aber auch aus Drehzahl, Ansaugdruck bzw. Ladedruck und Kraftstoffmasse ermittelt werden.
  • Ein weiteres Kennfeld liefert den NOX-Gehalt im unbehandelten Abgas.
The control unit 1 determines the catalyst efficiency and the NO x content in the untreated exhaust gas of the diesel engine 3 as follows:
  • Depending on the exhaust gas temperature and the amount of exhaust gas upstream of the catalytic converter, the map shows the catalyst efficiency. For this purpose, the amount of exhaust gas is determined from the intake air mass; but it can also be determined from the speed, intake pressure or boost pressure and fuel mass.
  • Another map provides the NO x content in the untreated exhaust gas.

Ausgehend von diesen Werten ergreift das Steuergerät bei zu hohem NOX-Ausstoß zwei Maßnahmen:

  • Durch Eingriff in die Steuerungsparameter für Einspritzbeginn, Abgasrückführrate, Schubabschaltung, Leerlaufdrehzahl, usw. wird der NOX-Gehalt im unbehandelten Abgas an den momentanen Katalysatorwirkungsgrad angepaßt, d.h. trotz eingeschränkter oder fehlender NOX-Reduktion wird eine überhöhter Schadstoffausstoß vermieden. Einzeln oder als Kombination kann der Einspritzbeginn verzögert, die Abgasrückführrate erhöht, die Schubabschaltung deaktiviert oder die Leerlaufdrehzahl angehoben werden.
  • Durch Veränderung der Steuerungsparameter wird die Abgastemperatur z.B. durch verzögertem Einspritzbeginn erhöht, um den Katalysator nach einem Kaltstart möglichst schnell auf Betriebstemperatur zu bringen bzw. ein zu starkes Abkühlen z.B. in Schubphasen zu verhindern.
Based on these values the control unit takes two actions at too high NO X emissions:
  • By intervening in the control parameters for the start of injection, exhaust gas recirculation rate, overrun fuel cut-off, idling speed, etc., the NO x content in the untreated exhaust gas is adapted to the current catalyst efficiency, that is, in spite of limited or no NO x reduction, excessive pollutant emissions are avoided. Individually or as a combination, the start of injection can be delayed, the exhaust gas recirculation rate increased, the overrun fuel cutoff deactivated or the idling speed increased.
  • By changing the control parameters, the exhaust gas temperature is increased, for example by delaying the start of injection, in order to bring the catalytic converter to operating temperature as quickly as possible after a cold start or to prevent excessive cooling, for example in overrun phases.

Die Auswirkung dieser Maßnahmen sind in Fig. 2 veranschaulicht. Kurve A zeigt den zeitlichen, von einer Prüfvorschrift (MVEG-Testzyklus) vorgegebenen Geschwindigkeitsverlauf, mit dem ein Testfahrzeug nach einem Kaltstart fährt. Kurve B zeigt den zeitlichen Verlauf der Katalysatortemperatur bei einer Abgasnachbehandlung nach dem Stand der Technik. Kurve C zeigt den zeitlichen Verlauf der Katalysatortemperatur beim erfindungsgemäßen Verfahren zur Verringerung des NOX-Gehaltes.The effects of these measures are illustrated in Fig. 2. Curve A shows the temporal speed curve, specified by a test specification (MVEG test cycle), with which a test vehicle drives after a cold start. Curve B shows the time course of the catalyst temperature in an exhaust gas aftertreatment according to the prior art. Curve C shows the course over time of the catalyst temperature in the process according to the invention for reducing the NO x content.

Der Geschwindigkeitsverlauf des MVEG-Testzyklus ist wie folgt: Zuerst wird ein für den Stadtverkehr typisches Geschwindigkeitsprofil mit mehrmaligem Beschleunigen, Abbremsen und Stillstand durchfahren. Eine beispielhafte Beschleunigungsphase ist mit b, eine Schubphase mit s bezeichnet. Nach 700 Sekunden wird mit höheren Geschwindigkeiten gefahren.The speed course of the MVEG test cycle is like follows: First, a speed profile typical for city traffic with repeated acceleration, braking and drive through standstill. An exemplary acceleration phase is denoted by b, an overrun phase by s. After 700 seconds are driven at higher speeds.

Kurve B zeigt den Verlauf der Katalysatortemperatur, die wie aus Fig. 3 bekannt mit dem Katalysatorwirkungsgrad verknüpft ist, bei einem Katalysator nach SCR-Prinzip. Es ist deutlich zu sehen, daß in Phasen des Abbremsens bzw. bei Stillstand des Testfahrzeuges die Temperatur abfällt. Das heißt, der Wirkungsgrad der katalytischen Nachbehandlung fällt ebenso, womit eine ansteigender NOX-Gehalt im behandelten Abgas einhergeht. Die Temperatur, bei der mit der Reduktionsmittelzugabe nach dem SCR-Prinzip begonnen werden kann, wird erst nach 300 Sekunden dauerhaft überschritten.Curve B shows the course of the catalyst temperature, which, as is known from FIG. 3, is linked to the catalyst efficiency in the case of a catalyst based on the SCR principle. It can be clearly seen that the temperature drops during phases of braking or when the test vehicle is at a standstill. That is, the efficiency of the catalytic after-treatment also falls, thus increasing a NOx content in the treated exhaust gas is accompanied. The temperature at which the addition of reducing agent can be started according to the SCR principle is only exceeded after 300 seconds.

Kurve C zeigt den Verlauf der Katalysatortemperatur nach einem Kaltstart beim erfindungsgemäßen Verfahren. Es wurden folgenden Eingriffe in die Steuerungsparameter durchgeführt:

  • In den Beschleunigungsphasen b wurde der Spritzbeginn gegenüber der üblicherweise verbrauchsoptimierten Abstimmung verzögert, was aufgrund der heißeren Abgase die Erwärmung des Katalysators beschleunigt. Dies resultiert in einem steileren Verlauf der Kurve C verglichen mit B. Zusätzlich ergibt sich durch den späteren Einspritzbeginn ein geringerer NOX-Gehalt im unbehandelten Abgas.
  • In Schubphasen s wird die Schubabschaltung deaktiviert, wodurch die in Kurve A erkennbaren Abkühlphasen vermieden werden und ein höheres Temperaturniveau viel schneller erreicht wird.
Curve C shows the course of the catalyst temperature after a cold start in the process according to the invention. The following interventions in the control parameters were carried out:
  • In acceleration phases b, the start of spraying was delayed compared to the customary consumption-optimized tuning, which accelerates the heating of the catalytic converter due to the hotter exhaust gases. This results in a steeper course of curve C compared to B. In addition, the later start of injection results in a lower NO x content in the untreated exhaust gas.
  • In overrun phases s the overrun fuel cutoff is deactivated, whereby the cooling phases recognizable in curve A are avoided and a higher temperature level is reached much faster.

Schon nach weniger als 180 Sekunden wird mit 120° die Temperatur überschritten, bei der mit der Reduktionsmittelzugabe nach dem SCR-Prinzip begonnen werden kann.After just less than 180 seconds, the temperature becomes 120 ° exceeded when adding the reducing agent can be started according to the SCR principle.

Die eingeleiteten Maßnahmen haben prinzipiell einen Kraftstoffmehrverbrauch zur Folge. Da sie aber nur bei unzureichender Katalysatortemperatur eingeleitet werden, was nur in Betriebsphasen mit geringer Motorlast und nach Kaltstart notwendig ist, ist dieser Mehrverbrauch im praktischen Fahrbetrieb sehr gering. Da ein schnelleres Aufheizen der Brennkraftmaschine aus Komfortgründen ohnehin erwünscht ist, kann dieser unwesentliche Mehrverbrauch akzeptiert werden.In principle, the measures introduced have an additional fuel consumption result. But since they are inadequate Catalyst temperature can be initiated, which is only in Operating phases with low engine load and after a cold start are necessary is, this additional consumption is in practical driving very low. Because the engine heats up faster is desired anyway for comfort reasons this insignificant additional consumption will be accepted.

Claims (7)

Verfahren zur Verringerung des NOX-Gehaltes im Abgas einer Dieselbrennkraftmaschine, mit einem Katalysator zur katalytischen Nachbehandlung des Abgases nach dem SCR-Prinzip, wobei dem Abgas stromauf des Katalysators ein Reduktionsmittel zugeführt wird, und mit einem Steuergerät, das Steuerungsparameter der Dieselbrennkraftmaschine, insbesondere den Einspritzbeginn des Kraftstoffes, die Leerlaufdrehzahl sowie den jeweiligen Katalysatorwirkungsgrad bestimmt und abhängig vom Katalysatorwirkungsgrad den Sollwert für die Reduktionsmittelzuführung berechnet, dadurch gekennzeichnet, daß bei Unterschreiten eines vorbestimmten Wertes für den Katalysatorwirkungsgrad abhängig vom Wert des Katalysatorwirkungsgrades vom Steuergerät (1) die Steuerungsparameter der Dieselbrennkraftmaschine so verändert werden, daß der NOX-Gehalt im unbehandelten Abgas verringert und die Abgastemperatur erhöht wird.Method for reducing the NO x content in the exhaust gas of a diesel internal combustion engine, with a catalyst for the catalytic aftertreatment of the exhaust gas according to the SCR principle, a reducing agent being supplied to the exhaust gas upstream of the catalyst, and with a control unit, the control parameters of the diesel internal combustion engine, in particular the The start of fuel injection, the idling speed and the respective catalyst efficiency are determined and, depending on the catalyst efficiency, the target value for the reducing agent supply is calculated, characterized in that the control unit (1) changes the control parameters of the diesel internal combustion engine as a result of the catalyst efficiency being below a predetermined value depending on the value of the catalyst efficiency be that the NO x content in the untreated exhaust gas is reduced and the exhaust gas temperature is increased. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß bei Unterschreiten des vorbestimmten Wertes der Einspritzzeitpunkt des Kraftstoffes verzögert wird.A method according to claim 1, characterized in that if the injection value falls below the predetermined value of the fuel is delayed. Verfahren nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß bei Unterschreiten des vorbestimmten Wertes die Leerlaufdrehzahl angehoben wird.A method according to claim 1 or 2, characterized in that that if the value falls below the predetermined value Idle speed is raised. Verfahren nach einem der Ansprüche 1 bis 3, für eine Dieselbrennkraftmaschine mit Abschaltung der Kraftstoffzufuhr im Schubbetrieb, dadurch gekennzeichnet, daß bei Unterschreiten des vorbestimmten Wertes die Schubabschaltung deaktiviert wird.Method according to one of claims 1 to 3, for a Diesel engine with fuel cut off in overrun mode, characterized in that when falling below of the predetermined value deactivates the fuel cut-off becomes. Verfahren nach einem der Ansprüche 1 bis 4, für eine Dieselbrennkraftmaschine mit Abgasrückführung, dadurch gekennzeichnet, daß bei Unterschreiten des vorbestimmten Wertes die Abgasrückführungsrate erhöht wird.Method according to one of claims 1 to 4, for a Diesel internal combustion engine with exhaust gas recirculation, characterized in that if the value falls below the predetermined value the exhaust gas recirculation rate is increased. Verfahren nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß der Katalysatorwirkungsgrad aus Steuerungsparametern, insbesondere des Abgasmassenstroms, und der gemessenen Abgastemperatur bestimmt wird.Method according to one of claims 1 to 5, characterized in that that the catalyst efficiency from control parameters, in particular the exhaust gas mass flow, and the measured Exhaust gas temperature is determined. Verfahren nach Anspruch 6, dadurch gekennzeichnet, daß der Abgasmassenstrom durch eine Modellrechnung mit Hilfe der Motordrehzahl und dem Ansaugdruck oder Ladedruck ermittelt wird.A method according to claim 6, characterized in that the exhaust gas mass flow through a model calculation using the Engine speed and the intake pressure or boost pressure determined becomes.
EP98119867A 1997-11-07 1998-10-20 Process for reducing the NOx content of Diesel engine exhaust gas Withdrawn EP0919702A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19749400A DE19749400C2 (en) 1997-11-07 1997-11-07 Process for reducing the NOX content in the exhaust gas of a diesel engine
DE19749400 1997-11-07

Publications (2)

Publication Number Publication Date
EP0919702A2 true EP0919702A2 (en) 1999-06-02
EP0919702A3 EP0919702A3 (en) 2001-08-16

Family

ID=7848030

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98119867A Withdrawn EP0919702A3 (en) 1997-11-07 1998-10-20 Process for reducing the NOx content of Diesel engine exhaust gas

Country Status (3)

Country Link
US (1) US6209313B1 (en)
EP (1) EP0919702A3 (en)
DE (1) DE19749400C2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007089401A1 (en) * 2006-01-31 2007-08-09 Caterpillar Inc. System for selective homogeneous charge compression ignition
AT516182A4 (en) * 2015-03-16 2016-03-15 Avl List Gmbh METHOD FOR DETERMINING THE CONCENTRATION OF AT LEAST ONE REACTION PRODUCT AT THE OUTPUT OF A CATALYST

Families Citing this family (43)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19817994A1 (en) * 1998-04-22 1999-11-04 Emitec Emissionstechnologie Method and device for purifying exhaust gas from an internal combustion engine containing nitrogen oxide (NO¶x¶)
DE60003627T2 (en) * 2000-01-05 2004-06-09 Robert Bosch Gmbh Process for controlling the heat loss of a catalytic converter during overrun
DE10010031B4 (en) * 2000-03-02 2011-06-09 Volkswagen Ag Method and device for carrying out a NOx regeneration of an arranged in an exhaust passage of an internal combustion engine NOx storage catalyst
US6427439B1 (en) * 2000-07-13 2002-08-06 Ford Global Technologies, Inc. Method and system for NOx reduction
US6502386B1 (en) * 2000-08-02 2003-01-07 Ford Global Technologies, Inc. Catalyst monitoring in a diesel engine
FR2812688B1 (en) * 2000-08-03 2003-04-04 Peugeot Citroen Automobiles Sa SYSTEM FOR AIDING THE REGENERATION OF A PARTICLE FILTER INTEGRATED IN AN EXHAUST LINE OF A DIESEL ENGINE OF A MOTOR VEHICLE
DE10118878A1 (en) * 2001-04-18 2002-10-31 Bosch Gmbh Robert Method for operating an internal combustion engine, in particular a motor vehicle
JP2002371888A (en) * 2001-06-18 2002-12-26 Isuzu Motors Ltd Engine warm-up control method
US6928359B2 (en) * 2001-08-09 2005-08-09 Ford Global Technologies, Llc High efficiency conversion of nitrogen oxides in an exhaust aftertreatment device at low temperature
US7121085B2 (en) * 2001-09-04 2006-10-17 Ford Global Technologies, Llc Method and apparatus for controlling hydrocarbon injection into engine exhaust to reduce NOx
DE10148661C2 (en) * 2001-10-02 2003-12-24 Daimler Chrysler Ag Method and device for controlling an exhaust aftertreatment system
JP3861733B2 (en) * 2002-04-04 2006-12-20 トヨタ自動車株式会社 Exhaust gas purification device for internal combustion engine
US6810661B2 (en) * 2002-08-09 2004-11-02 Ford Global Technologies, Llc Method and system for freeze protecting liquid NOx reductants for vehicle application
US20040083721A1 (en) * 2002-11-06 2004-05-06 Ford Global Technologies, Inc. Diesel aftertreatment systems
US20040083722A1 (en) * 2002-11-06 2004-05-06 Ford Global Technologies, Inc. Diesel aftertreatment systems
US6871490B2 (en) * 2002-12-19 2005-03-29 Caterpillar Inc Emissions control system for increasing selective catalytic reduction efficiency
EP1477655A1 (en) * 2003-05-13 2004-11-17 Haldor Topsoe A/S Process for controlled addition of a reducing agent into nitrogen oxides containing exhaust gas
US6901748B2 (en) * 2003-05-14 2005-06-07 Detroit Diesel Corporation Heater system for diesel engines having a selective catalytic reduction system
DE10338628A1 (en) 2003-08-22 2005-03-17 Daimlerchrysler Ag Method for operating an internal combustion engine with emission control system
US7067319B2 (en) * 2004-06-24 2006-06-27 Cummins, Inc. System for diagnosing reagent solution quality and emissions catalyst degradation
DE102004050989B4 (en) * 2004-10-20 2015-06-25 Robert Bosch Gmbh Method for operating an exhaust gas treatment device of an internal combustion engine and device for carrying out the method
ITMI20050601A1 (en) * 2005-04-11 2006-10-12 Iveco Spa METHOD AND CONTROL SYSTEM FOR A SCR SYSTEM EQUIPPED
FR2902140B1 (en) 2006-06-07 2008-09-12 Peugeot Citroen Automobiles Sa METHOD FOR MANAGING THE OPERATION OF AN INTERNAL COMBUSTION ENGINE AND ITS EXHAUST LINE
US7587889B2 (en) * 2006-07-11 2009-09-15 Cummins Filtration Ip, Inc. System for determining NOx conversion efficiency of an exhaust gas aftertreatment component
US7930878B2 (en) * 2007-02-27 2011-04-26 Ford Global Technologies, Llc Method and apparatus for rapidly thawing frozen NOx reductant
US8171724B2 (en) * 2007-05-02 2012-05-08 Ford Global Technologies, Llc Vehicle-based strategy for removing urea deposits from an SCR catalyst
US7967720B2 (en) * 2007-06-13 2011-06-28 Ford Global Technologies, Llc Dynamic allocation of drive torque
US7966812B2 (en) * 2007-08-29 2011-06-28 Ford Global Technologies, Llc Multi-stage regeneration of particulate filter
US9429090B2 (en) * 2008-06-04 2016-08-30 Fca Us Llc Method of estimating catalyst temperature of a multi-displacement internal combustion engine
US8201444B2 (en) 2008-08-19 2012-06-19 GM Global Technology Operations LLC Aftertreatment device NOx conversion efficiency diagnostics using on board adaptive diagnostic algorithm
DE102009007765A1 (en) 2009-02-06 2010-08-12 Daimler Ag Method for operating an internal combustion engine with an exhaust gas purification system comprising an SCR catalytic converter
DE102009007764A1 (en) 2009-02-06 2010-08-12 Daimler Ag Method for operating an internal combustion engine with an emission control system
US8245502B2 (en) * 2009-06-16 2012-08-21 Ford Global Technologies, Llc Emission control system with an optimized reductant injection model
US8745973B2 (en) * 2009-08-20 2014-06-10 GM Global Technology Operations LLC System and method for controlling reducing agent injection in a selective catalytic reduction system
CA2702246C (en) * 2010-04-20 2012-01-17 Westport Power Inc. Method of controlling a direct-injection gaseous-fuelled internal combustion engine system with a selective catalytic reduction converter
FR3014493B1 (en) * 2013-12-05 2017-12-08 Peugeot Citroen Automobiles Sa METHOD OF OPTIMIZING THE DETECTION OF A FAILING CATALYST
DE102016219561B4 (en) * 2016-10-07 2023-02-23 Vitesco Technologies GmbH Method for controlling an internal combustion engine in a motor vehicle
JP6734796B2 (en) * 2017-02-24 2020-08-05 三菱重工業株式会社 Marine diesel engine and engine control device and method
FR3069574B1 (en) 2017-07-25 2019-08-02 Continental Automotive France METHOD FOR ADAPTING A QUANTITY OF REDUCING AGENT FOR GAS NITROGEN OXIDE DEPOLLUTION IN AN ENGINE EXHAUST LINE
CN111120126B (en) * 2019-12-31 2022-07-15 潍柴动力股份有限公司 Emission method, device and system for extended range vehicle
US11428181B2 (en) 2020-03-25 2022-08-30 Cummins Inc. Systems and methods for ultra-low NOx cold start warmup control and fault diagnosis
US11732628B1 (en) 2020-08-12 2023-08-22 Old World Industries, Llc Diesel exhaust fluid
CN113756918B (en) * 2021-09-23 2022-10-04 湖南道依茨动力有限公司 Engine control method, engine control device and vehicle

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4436415A1 (en) 1994-10-12 1996-04-18 Bosch Gmbh Robert Device for the aftertreatment of exhaust gases from a self-igniting internal combustion engine

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1298957C (en) * 1987-01-27 1992-04-21 Motonobu Kobayashi Method for removal of nitrogen oxides from exhaust gas of diesel engine
DE4203807A1 (en) * 1990-11-29 1993-08-12 Man Nutzfahrzeuge Ag Catalytic nitrogen oxide(s) redn. appts. for vehicles - comprises flow mixer urea evaporator hydrolysis catalyst, for exhaust gas treatment
JP2887933B2 (en) * 1991-03-13 1999-05-10 トヨタ自動車株式会社 Exhaust gas purification device for internal combustion engine
WO1992021871A1 (en) * 1991-06-03 1992-12-10 Isuzu Motors Limited DEVICE FOR REDUCING NO¿x?
DE4315278A1 (en) * 1993-05-07 1994-11-10 Siemens Ag Method and device for metering a reducing agent into a nitrogen-containing exhaust gas
DE4334071C1 (en) * 1993-10-06 1995-02-09 Siemens Ag Process for reducing the nitrogen oxide concentration in the exhaust gas of an internal combustion engine or a combustion plant
ES2140700T3 (en) * 1994-09-13 2000-03-01 Siemens Ag PROCEDURE AND DEVICE FOR INTRODUCING LIQUID IN AN EXHAUST GAS DEPURATION DEVICE.
JPH08121154A (en) * 1994-10-24 1996-05-14 Komatsu Ltd Method and apparatus for purifying engine exhaust gas
JP3391587B2 (en) * 1994-11-18 2003-03-31 株式会社小松製作所 Exhaust denitration equipment for diesel engines
JPH08270435A (en) * 1995-03-29 1996-10-15 Nissan Diesel Motor Co Ltd Exhaust emission control device for diesel engine
JPH08284647A (en) * 1995-04-10 1996-10-29 Nippon Soken Inc HC increase device attached to an exhaust purification device of an internal combustion engine
ATE177509T1 (en) * 1995-09-29 1999-03-15 Siemens Ag METHOD AND DEVICE FOR CONVERTING A POLLUTANT IN AN EXHAUST GAS ON A CATALYST
JPH09195755A (en) * 1996-01-17 1997-07-29 Toyota Motor Corp Exhaust gas purification device for internal combustion engine
DE19629163C1 (en) * 1996-07-19 1997-10-09 Daimler Benz Ag Diesel engine operation to suppress nitrogen oxides emission
JPH1047048A (en) * 1996-08-02 1998-02-17 Toyota Motor Corp Exhaust gas purification device for internal combustion engine
JP3465490B2 (en) * 1996-09-09 2003-11-10 トヨタ自動車株式会社 Exhaust gas purification device for internal combustion engine

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4436415A1 (en) 1994-10-12 1996-04-18 Bosch Gmbh Robert Device for the aftertreatment of exhaust gases from a self-igniting internal combustion engine

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
"Bewertung der stöchiometrischen benzindirekteinspritzer- motorentechnologie", 1997, AVL-TAGUNG MOTOT UND UMWELT, pages: 106

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007089401A1 (en) * 2006-01-31 2007-08-09 Caterpillar Inc. System for selective homogeneous charge compression ignition
AT516182A4 (en) * 2015-03-16 2016-03-15 Avl List Gmbh METHOD FOR DETERMINING THE CONCENTRATION OF AT LEAST ONE REACTION PRODUCT AT THE OUTPUT OF A CATALYST
AT516182B1 (en) * 2015-03-16 2016-03-15 Avl List Gmbh METHOD FOR DETERMINING THE CONCENTRATION OF AT LEAST ONE REACTION PRODUCT AT THE OUTPUT OF A CATALYST

Also Published As

Publication number Publication date
EP0919702A3 (en) 2001-08-16
DE19749400A1 (en) 1999-05-20
US6209313B1 (en) 2001-04-03
DE19749400C2 (en) 2001-11-29

Similar Documents

Publication Publication Date Title
DE19749400C2 (en) Process for reducing the NOX content in the exhaust gas of a diesel engine
DE60314360T2 (en) Emission control system for increasing the performance of a selective catalytic reduction
DE102011080625B4 (en) METHOD FOR REDUCING UREA DEPOSITS IN A POST-TREATMENT SYSTEM
DE102008018063B4 (en) Vehicle-based strategy for removing urea deposits from an SCR catalytic converter
DE102006057325B4 (en) exhaust gas purification device
DE102009011469B4 (en) Fault control strategy for urea SCR NOX reduction at low temperatures
DE69917990T2 (en) Device for exhaust gas purification for an internal combustion engine
EP2394044B1 (en) Method for the operation of an internal combustion engine comprising an emission control system that includes an scr catalyst
DE102014212741A1 (en) AMMONIA REPORT MANAGEMENT FOR SCR CATALYST
DE102011018929B4 (en) Control system to prevent hydrocarbon slip during regeneration of a particulate filter
DE102010030651A1 (en) Controlling the regeneration of an exhaust gas purification device
DE102009041688B4 (en) Particle filter regeneration temperature control system and method using a hydrocarbon injector
DE102016014854A1 (en) Process for exhaust aftertreatment
DE102017127473A1 (en) Process for exhaust aftertreatment of an internal combustion engine
DE102015213892A1 (en) LNT control with an adaptive cruise control
DE102011105601B4 (en) A control system for regenerating a particulate matter filter using a catalytic converter as a combustor
DE102017006514B4 (en) Exhaust emission control system, method for controlling an exhaust emission system and computer program product
EP0639708B1 (en) Method for operating a vehicular internal combustion engine
DE102011011841A1 (en) Method and system for controlling an engine during diesel particulate filter regeneration at idle conditions
EP3167171B1 (en) Method for operating a reducing agent dosing of an scr catalyst system, and corresponding scr catalyst system
DE102010056454B4 (en) A method of controlling a diesel engine during regeneration of a diesel particulate filter
DE102013001424B4 (en) Intake and exhaust device of a multi-cylinder engine and internal combustion engine
DE60018863T2 (en) Method and apparatus for purifying exhaust gases from motor vehicle engines
DE102020101194B4 (en) Process for exhaust aftertreatment of an internal combustion engine and internal combustion engine
DE102022121068A1 (en) Emission control for lean burn engines

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT DE FR IT

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

RIC1 Information provided on ipc code assigned before grant

Free format text: 7F 01N 3/20 A, 7B 01D 53/94 B, 7F 02D 21/08 B, 7F 02D 31/00 B

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 20011023

AKX Designation fees paid

Free format text: AT DE FR IT

17Q First examination report despatched

Effective date: 20020923

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20040316